Glucose sensing is a critical step towards the timely diagnosis and treatment of diabetes, which is one of the major diseases with great clinical attentions. There have been intensive research and well-developed commercialized products to easily and accurately monitor a blood glucose level. Non-invasive or minimally invasive glucose monitoring has been considered as one of the vital concerns for clinical applications, due to the need of frequent monitoring and the inconveniences of blood sampling. Therefore, a simpler and more reliable approach is desired, especially in terms of the sensitivity to a very small-volume body fluid.
Carbon nanotube devices have been employed in a range of chemical and biological sensor applications. See, U.S. Pat. No. 6,528,020, the entirety of which is incorporated herein by reference. However, such devices are described in the '020 patent only in the most general terms. Glucose sensing, for example, is mentioned prospectively, without regard to device configuration or mode of operation. The search for a reliable, accurate glucose sensor continues to be a concern in the art. More recently and in more detail, carbon nanotubes, have been proposed for potentially high-sensitivity monitoring of glucose, but overall performance and sufficient specificity for practical applications remain to be proven. [K. Besteman, J. Lee, F. G. M. Wiertz, H. a. Heering, and C. Dekker, “Enzyme-Coated Carbon Nanotubes as Single-Molecule Biosensors,” Nano lett., vol. 3, pp. 727–730, 2003.]